Wednesday 19 September 2007 08.30 EDT
First published on Wednesday 19 September 2007 08.30 EDT

There was no disguising the relief - the euphoria even - in the Menzies Campbell camp last night when news began to circulate in Brighton that the Guardian's latest poll had put the Liberal Democrats back up to 20%. This is a conference and a party under siege, struggling to come to terms with the challenges of David Cameron and Gordon Brown, and whose confidence is slowly draining away after the advances of 1997-2005. The downward drift in the party's standing may not be Ming's fault, but it is happening on his watch and when things go wrong it is the boss who carries the can. So the boost in the Guardian ICM poll from 18% in August to 20% today lifted Campbell's spirits by far more than 2%.

Unless there is an early general election, however, the Lib Dem leadership question is not going to disappear. The longer Brown waits, the more space he allows for Lib Dems to wonder whether a new leader might save them seats which otherwise, even on a 20% share of the poll, the party now looks likely to lose. Some MPs in the Lib Dem marginals think Ming and the earlier generation of well dug-in Lib Dem MPs don't understand how vulnerable things are in the southern - and some northern - seats that the party captured in the last decade. I think it is more likely than not that Ming will have gone by this time next year, either because it will be time for a change after an early election or because MPs will gamble that a new face might save their seats in a delayed election in 2009 or 2010.

When the moment comes, it is beyond doubt that Nick Clegg and Chris Huhne will be the favourites to succeed Campbell. Clegg's comment last night that he would run if and when there is a vacancy confirms his interest. And Huhne, who ran Campbell unexpectedly close in the contest to succeed Charles Kennedy in 2006, has never made any secret of his ambitions either, however censoriously he dismissed the idea today when asked to comment on Clegg's remarks. Don't rule out the possibility of other contenders - but the head-to-head between Clegg and Huhne is what the party and the press is expecting, and it is certainly what they will get. Both men are up for it.

It is sometimes said that Clegg and Huhne are the Blair and Brown of the Liberal Democrats. The comparison can be a useful one. Clegg, the Blair of the pairing, has the easy manner, the televisual appeal and - crucially - the focused determination to reach out beyond Fortress Liberal Democrat for new electoral support. Huhne, the Brown of the analogy, is the brainier one, the more experienced, is more calculating and in some respects the more ideologically comfortable for the party - especially the part of it which derives, as Huhne himself does, from the SDP social democratic tradition of the 1970s and 1980s.

As with Blair and Brown, the political similarities between Clegg and Huhne - on Europe, civil liberties, devolution and the rest (including the refusal to enter a coalition government) - greatly outweigh the differences of habit and style. But there are strategic differences too. Clegg is fixated on reaching new supporters by tackling new issues that make traditionalists uneasy - immigration this week has been a case in point. He wants to move the party away from its comfort zone, which he sometimes finds too puritanical, towards grittier issues that trouble the voters more than they trouble many Lib Dem members. Huhne, on the other hand, is committed to the more social democratic approach with which many in the party are extremely comfortable - redistributive tax policies, the centrality of public services to achieve social justice and a more root-and-branch approach to green issues. Clegg supporters think Huhne is insufficiently radical in his thinking. Huhne supporters think Clegg is insufficiently clear.

In the end, the contest between the two men will come down to how the Liberal Democrat membership judges them as election winners and as keepers of the flame. The two criteria can sometimes act against each other and much will depend upon whether, when the contest comes, the party is more frightened about its possible election losses or about its sense of its own political purity. If the contest is about saving seats and getting back on the attack, then Clegg could be the favourite. If the contest is about re-energising the party with the old-time religion, then Huhne may be the victor. But both men are confident they will win. Inevitably, all this is an over-simplication in many ways. The simple truth is that both Clegg and Huhne are notable political talents with inevitable flaws. But the contest will happen - and on the evidence from Brighton it will happen sooner than we think.

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